This invention relates to a light-sensitive silver halide color photographic material, more particularly to a light-sensitive silver halide color photographic material which can be subjected to rapid developing processing, is improved in processing stability in said rapid developing processing, can be saved in silver and can be suppressed in generation of fog, and yet is capable of giving a color image of good light resistance (fastness to light).
Generally speaking, a light-sensitive silver halide color photographic material has three kinds of silver halide emulsion layers spectrally sensitized selectively so as to have sensitivity to blue light, green light and red light provided by coating on a support. For example, in a light-sensitive silver halide color photographic material for color negative, a blue-sensitive silver halide emulsion layer, a green-sensitive silver halide emulsion layer and a red-sensitive silver halide emulsion layer are generally provided by coating in this order from the side exposed, and a bleachable yellow filter layer is provided between the blue-sensitive silver halide emulsion layer and the green-sensitive silver halide emulsion layer for absorption of the blue light transmitted through the blue-sensitive silver halide emulsion layer. Further, it is practiced to provide other intermediate layers for various special purposes between the respective emulsion layers, and also a protective layer as the outermost layer. Further, for example, in a light-sensitive silver halide color photographic material for color printing paper, a red-sensitive silver halide emulsion layer, a green-sensitive silver halide emulsion layer and a blue-sensitive silver halide emulsion layer are generally provided by coating in this order from the side exposed, and there are also provided various intermediate layers for various special purposes, typically UV-ray absorbing layer, and a protective layer, etc., similarly as in the case of the light-sensitive silver halide color photographic material for color negative. These respective silver halide emulsion layers are also known to be provided in an arrangement different from those as mentioned above, and it is also known to use a light-sensitive silver halide emulsion layer comprising two layers having sensitivities to substantially the same wavelength regions relative to the respective color lights. In these light-sensitive silver halide color photographic material, the exposed silver halide grains are developed by using, for example, an aromatic primary amine type color developing agent as the color developing agent, and color images are formed through the reaction of the oxidized product of the color developing agent formed with a dye forming coupler. In this method, since dye images of cyan, magenta and yellow are generally formed, phenol or naphthol type cyan couplers, 5-pyrazolone type, pyrazolinobenzimidazole type, pyrazolotriazole type, indazolone type or cyanoacetyl type magenta couplers and acylacetamide type yellow couplers are used, respectively. These dye forming couplers are contained in the light-sensitive silver halide emulsion layers or developing solutions. This invention concerns a light-sensitive silver halide color photographic material in which these couplers are made non-diffusible and previously contained in the silver halide emulsion layers.
In recent years, in this field of the art, it has been desired to have a light-sensitive silver halide color photographic material, which can be processed rapidly, can give high image quality, is yet excellent in processing stability and can be produced at low cost, particularly a light-sensitive silver halide color photographic material which can be processed rapidly.
More specifically, it has been practiced to subject light-sensitive silver halide color photographic materials to running processing by means of automatic processing machines provided in respective laboratories. As a part for improvement of services for users, it is demanded to return the material subjected to the processing within the very day on which the order for processing is received. Quite recently, it became demanded to return the processed material within several hours from the receipt of order. Thus, development for light-sensitive silver halide color photographic materials capable of increasingly rapid processing is imminently demanded. Also, in running processing, between the respective laboratories or even in the same laboratory, photographic characteristics will be greatly changed due to the changes in compositions of processing solutions and fluctuations in conditions, thus involving a problem that stable photographic performances cannot be obtained. Such changes in compositions of processing solutions and fluctuations in conditions may be considered to be due to dissolution or accumulation of photographic active substances from the light-sensitive material during developing processing (running) or other causes. Thus, in order to accommodate fluctuations in processing conditions, it is required to highly control the developing time, the temperature and the pH of the developing solution, further the halogen concentration, particularly the bromo ion concentration, etc. in the developing solution. However, as compared with developing time or temperature and pH of the developing solution, the bromo ion concentration in the developing solution can be quantitated with difficulty to be poor in measurability, whereby it can be controlled with difficulty. Accordingly, it is particularly required to develop a light-sensitive silver halide color photographic material which is highly stabilized in processing with its photographic performanced being little dependent on the bromo ion concentration. Although there is also generally involved a problem in processing time, processing stability is a greater problem in rapid processing. Further, it is demanded that the light-sensitive silver halide color photographic material thus stabilized in processing should be provided economically at low cost, as a matter of course.
Now, to review the prior art techniques concerning light-sensitive silver halide color photographic materials enabling rapid processing, there have been known (1) the micropulverization technique of silver halide as disclosed in Japanese Unexamined Patent Publication No. 77223/1976; (2) the technique for reduction of silver bromide in silver halide as disclosed in Japanese Unexamined Patent Publication No. 184142/1983 and Japanese Patent Publication No. 18939/1981; the technique for adding 1-aryl-3-pyrazolidone having a specific structure to a light-sensitive silver halide color photographic material as disclosed in Japanese Unexamined Patent Publication No. 64339/1981, further the techniques for adding 1-arylpyrazolidones to light-sensitive silver halide color photographic materials as disclosed in Japanese Unexamined Patent Publications Nos. 144547/1982, 50534/1983, 50535/1983 and 50536/1983; and otherwise (4) the technique to employ a color developing promoter in carrying out development of the exposed light-sensitive silver halide color photographic material with the use of an aromatic primary amine type color developing agent. For example, such color developing promotors may include the compounds as disclosed in U.S. Pat. Nos. 2,950,970, 2,515,147, 2,496,903, 4,038,075 and 4,119,462; U.K. Patent Nos. 1,430,998 and 1,455,413; Japanese Unexamined Patent Publications Nos. 15831/1978, 62450/1980, 62451/1980, 62452/1980 and 62453/1980; Japanese Patent Publications Nos. 12422/1976 and 49728/1980.
However, among these prior art techniques, when (3) or (4) is employed, although the processing time can be shortened, processing stability is poor in said rapid developing processing, and there is also involved a problem in the instant day performance.
And, when the reduced silver bromide emulsion of the above (2) is employed, although the bromo ion concentration in the processing solution can be set at a low level on account of the small amount of the bromo ions dissolved into the processing solution from the light-sensitive silver halide color photographic material containing said reduced silver bromide emulsion, there is involved the drawback that processing stability is poor when the light-sensitive silver halide color photographic material containing the reduced silver bromide emulsion is processed by use of a processing solution in which the bromo ion concentration is set at a low level. Here, processing stability refers to the degree of fluctuation in sensitometry to fluctuations in processing solution composition, pH, temperature, bromo ion concentration, etc. and entrainment of compounds other than the processing solution composition.
Also, when the micropulverized silver halide of the above (1) is employed, there is involved the drawback of inferior processing stability, and there is also observed the drawback that sensitivity is impaired as the grains become finer.
On the other hand, as for the prior art techniques for improvement of processing stability, there are techniques by way of improvement of processing solutions, as disclosed in Japanese Unexamined Patent Publications Nos. 121036/1984 and 120250/1984. However, to the best knowledge of the present inventors, there is no example in which processing stability is substantially improved by improvement of light-sensitive silver halide color photographic material, and it has been desired to develop a technique for improvement of processing stability by way of improvement of said light-sensitive material.
On the other hand, silver saving is a technical means for providing a light-sensitive silver halide color photographic material at low cost. Various techniques capable of effecting silver saving have been known, and use of a pyrazolotriazole type magenta coupler is one of the main techniques for silver saving. However, as a problem of a pyrazolotriazole type magenta coupler, a drawback has been pointed out that generation of fog in the instant day performance is high.
In order to overcome this problem, various attempts for improvement have been made. For example, there is a technique in which fog is inhibited by addition of an inhibitor, as disclosed in the Japanese Patent Application filed by the present Applicant on Sept. 1, 1984 (Title of the invention: Light-sensitive silver halide photographic material).
However, fog inhibition with an inhibitor will cause undesirably substantial lowering in sensitivity. Therefore, it has been desired to develop a light-sensitive silver halide color photographic material with little generation of fog.
Accordingly, the present inventors have previously proposed a technique as disclosed in Japanese Patent Application No. 202063/1984. Such a previously proposed technique is a light-sensitive silver halide color photographic material having a blue-sensitive silver halide emulsion layer, a green-sensitive silver halide emulsion layer and a red-sensitive silver halide emulsion layer on a support, wherein the mean grain size of the silver halide in the blue-sensitive silver halide emulsion layer is 0.20 to 0.55 .mu.m, the content of silver bromide of the silver halides in said green-sensitive silver halide emulsion layer and red-sensitive silver halide emulsion layer is 5 to 65 mole %, and said green-sensitive silver halide emulsion layer contains at least one of the compounds represented by the formula [A] shown below: ##STR2## wherein R.sub.5 represents a halogen atom or a monovalent organic group eliminable through coupling reaction with the oxidized product of a developing agent. R.sub.6 and R.sub.7, which may be either identical or different, each represent a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, an acylamino group, an alkylamino group, an anilino group, an alkoxycarbonyl group, an alkylthio group, with proviso that R.sub.6 and R.sub.7 cannot be hydrogen atoms at the same time.
According to such a previously proposed technique, it is surely possible to provide a light-sensitive silver halide color photographic material which is capable of performing rapid developing processing, is improved in processing stability in said rapid developing, is capable of effecting silver saving, and also can inhibit generation of fog.
The present inventors have further continued to study about the above previously proposed technique and found out the following points.
Most of the couplers which were provided widely in practical applications as magenta dye image forming couplers and under progress of study in the prior art were 5-pyrazolones. The dyes formed from 5-pyrazolone type couplers are excellent in fastness to heat and light, but there exists an unnecessary absorption having a yellow component in the vicinity of 430 nm, which causes color turbidity.
As the coupler skeltal nucleus for forming a magenta dye image which can reduce the yellow component, a pyrazolobenzimidazole skeltal nucleus as disclosed in U.K. Patent No. 1,047,612, an indazolone skeltal nucleus as disclosed in U.S. Pat. No. 3,770,447 and a pyrazolotriazole skeltal nucleus have been known.
Among them, the dye formed from the 1H-pyrazolo[3,2-c]-s-triazole type coupler is little in unnecessary absorption in the vicinity of 430 nm in a solvent such as ethyl acetate, dibutyl phthalate, etc., and besides excellent in sharp cut characteristic on the longer wavelength side, but fastness to light of the azomethyne dye is markedly low, whereby performances of light-sensitive color photographic materials, particularly print type light-sensitive color photographic materials, are markedly impaired.